using System;

public class Program

{

    public static void Main()

    {

        int [,] mat =new int [6,6];

        Random r= new Random();

        for (int i=0 ;i<6 ;i++){

            for (int j=0; j<6; j++){

                mat[i,j]=r.Next(100,500);

            Console.Write(mat[i,j]+" ");

            }

            Console.WriteLine("");

        }

        Console.WriteLine("\n\n");

            string t ="";

        for (int i=0 ;i<6 ;i++){

            Console.Write(t);

            for (int j=i; j<6; j++){                    

                    Console.Write(mat[i,j]+" ");

            }

            t+="    ";

            Console.WriteLine(t);

        }

                Console.WriteLine("\n\n");

​

        for(int i=0;i<mat.GetLength(0);i++){

            for(int j=0;j<mat.GetLength(1);j++){

                if(i==0||i==mat.GetLength(0)-1||j==0||j==mat.GetLength(1)-1){

                Console.Write(mat[i,j]+" ");

                }else{

                Console.Write("    ");

​

                }

        }

            Console.WriteLine("");

    }

    }

}